(1) Field of the Invention
The present invention relates to a gene sequence-reading instrument for reading the four bases of A, C, G, and U of the single stranded ribonucleic acid (RNA).
(2) Description of the Related Art
In the conventional DNA sequencers, a DNA was enzymatically cleaved at specific sequence region, a fluorophore was linked to the end of the cleaved region by a synthetic reaction, DNA was allowed to migrate at one direction by electrophoresis, and the length of the DNA was estimated by a laser beam from the time required for the migration. In this method, although the base at the end portion can be identified by an enzyme used for cleaving, bases in the remaining portion are completely unknown. Thus, the method required the sequencing of the end portion by cleaving the same DNA with various enzymes, and the reconstitution of the original DNA using a large scale computer.
DNA chips utilize the property that when RNA having a known sequence is spotted on a glass substrate, and the subject DNA is contaminated into the spotted region, the subject DNA can bind to the RNA of the known sequence only when the DNA has the consensus sequence with the RNA having the known sequence. Thus, sequences were estimated by spotting a variety of RNAs of known sequences and then detecting the presence or absence of the binding to the subject DNA. In either case, the coding sequence of the subject DNA cannot be directly read.
The conventional technology of DNA sequencers and DNA chips had the problems that they required the fragmentation of the original DNA, and even if the fragmented DNA sequences were partially identified, it was not easy to restore the original DNA. Thus, the total throughput required long hours, and besides the reliability of the restored DNA sequence was questioned.